Uni-Bayreuth grafik-uni-bayreuth



Drought and heavy rainfall alter biotic interactions among plants

Kerstin Grant1, Anke Jentsch1, Jürgen Kreyling2, Carl Beierkuhnlein2
1 Störungsökologie & Vegetationsdynamik, Uni Bayreuth
2 Biogeografie, Uni Bayreuth

O 4.4 in Klimaforschung

02.04.2009, 17:00-17:15, H8

Extreme weather events are projected to increase in frequency and magnitude in the near future due to global climate change – however there is not much known about their effects on biotic interactions, plant community composition and ecosystem functioning. In the field experiment EVENT I grassland communities are exposed to  100-year recurrent drought and heavy rain events during the vegetation period. The plant communities are variations of the species Arrhenatherum elatius, Holcus lanatus, Plantago lanceolata, Geranium pratense and Lotus corniculatus with increasing number of species and functional groups. Here, we present first results how extreme drought and heavy rain affect the biotic interactions among various grassland species. Their competitive balance was altered by extreme events. Heavy rainfall significantly enhanced overall competition, however facilitation by neighbouring plants was neither observed under drought nor under heavy rain except for one species. The presence of legumes in plant communities led to higher relative crowding which influenced the relative neighbour effect. These findings are a helpful tool in analysing alterations in plant performance under changing climate. This research will be continued within the sub-project 8 of the research cooperation FORKAST, which is part of the Bavarian climatic program Bayern 2020 and aims to investigates the climatic effects on ecosystems an climatic adaptation strategies.

Letzte Änderung 06.03.2009